tile/perf: Support perf_events on tilegx and tilepro
Add perf support for tile architecture.
Signed-off-by: Zhigang Lu <zlu@tilera.com>
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
diff --git a/arch/tile/Kconfig b/arch/tile/Kconfig
index 3067b15..31c8c62 100644
--- a/arch/tile/Kconfig
+++ b/arch/tile/Kconfig
@@ -3,6 +3,8 @@
config TILE
def_bool y
+ select HAVE_PERF_EVENTS
+ select USE_PMC if PERF_EVENTS
select HAVE_DMA_ATTRS
select HAVE_DMA_API_DEBUG
select HAVE_KVM if !TILEGX
diff --git a/arch/tile/include/asm/perf_event.h b/arch/tile/include/asm/perf_event.h
new file mode 100644
index 0000000..59c5b16
--- /dev/null
+++ b/arch/tile/include/asm/perf_event.h
@@ -0,0 +1,22 @@
+/*
+ * Copyright 2014 Tilera Corporation. All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ * NON INFRINGEMENT. See the GNU General Public License for
+ * more details.
+ */
+
+#ifndef _ASM_TILE_PERF_EVENT_H
+#define _ASM_TILE_PERF_EVENT_H
+
+#include <linux/percpu.h>
+DECLARE_PER_CPU(u64, perf_irqs);
+
+unsigned long handle_syscall_link_address(void);
+#endif /* _ASM_TILE_PERF_EVENT_H */
diff --git a/arch/tile/kernel/Makefile b/arch/tile/kernel/Makefile
index 71d8353..21f77bf 100644
--- a/arch/tile/kernel/Makefile
+++ b/arch/tile/kernel/Makefile
@@ -25,6 +25,7 @@
else
obj-$(CONFIG_PCI) += pci.o
endif
+obj-$(CONFIG_PERF_EVENTS) += perf_event.o
obj-$(CONFIG_USE_PMC) += pmc.o
obj-$(CONFIG_TILE_USB) += usb.o
obj-$(CONFIG_TILE_HVGLUE_TRACE) += hvglue_trace.o
diff --git a/arch/tile/kernel/irq.c b/arch/tile/kernel/irq.c
index 0586fdb..906a76b 100644
--- a/arch/tile/kernel/irq.c
+++ b/arch/tile/kernel/irq.c
@@ -21,6 +21,7 @@
#include <hv/drv_pcie_rc_intf.h>
#include <arch/spr_def.h>
#include <asm/traps.h>
+#include <linux/perf_event.h>
/* Bit-flag stored in irq_desc->chip_data to indicate HW-cleared irqs. */
#define IS_HW_CLEARED 1
@@ -261,6 +262,23 @@
}
/*
+ * /proc/interrupts printing:
+ */
+int arch_show_interrupts(struct seq_file *p, int prec)
+{
+#ifdef CONFIG_PERF_EVENTS
+ int i;
+
+ seq_printf(p, "%*s: ", prec, "PMI");
+
+ for_each_online_cpu(i)
+ seq_printf(p, "%10llu ", per_cpu(perf_irqs, i));
+ seq_puts(p, " perf_events\n");
+#endif
+ return 0;
+}
+
+/*
* Generic, controller-independent functions:
*/
diff --git a/arch/tile/kernel/perf_event.c b/arch/tile/kernel/perf_event.c
new file mode 100644
index 0000000..2bf6c9c
--- /dev/null
+++ b/arch/tile/kernel/perf_event.c
@@ -0,0 +1,1005 @@
+/*
+ * Copyright 2014 Tilera Corporation. All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ * NON INFRINGEMENT. See the GNU General Public License for
+ * more details.
+ *
+ *
+ * Perf_events support for Tile processor.
+ *
+ * This code is based upon the x86 perf event
+ * code, which is:
+ *
+ * Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de>
+ * Copyright (C) 2008-2009 Red Hat, Inc., Ingo Molnar
+ * Copyright (C) 2009 Jaswinder Singh Rajput
+ * Copyright (C) 2009 Advanced Micro Devices, Inc., Robert Richter
+ * Copyright (C) 2008-2009 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
+ * Copyright (C) 2009 Intel Corporation, <markus.t.metzger@intel.com>
+ * Copyright (C) 2009 Google, Inc., Stephane Eranian
+ */
+
+#include <linux/kprobes.h>
+#include <linux/kernel.h>
+#include <linux/kdebug.h>
+#include <linux/mutex.h>
+#include <linux/bitmap.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/perf_event.h>
+#include <linux/atomic.h>
+#include <asm/traps.h>
+#include <asm/stack.h>
+#include <asm/pmc.h>
+#include <hv/hypervisor.h>
+
+#define TILE_MAX_COUNTERS 4
+
+#define PERF_COUNT_0_IDX 0
+#define PERF_COUNT_1_IDX 1
+#define AUX_PERF_COUNT_0_IDX 2
+#define AUX_PERF_COUNT_1_IDX 3
+
+struct cpu_hw_events {
+ int n_events;
+ struct perf_event *events[TILE_MAX_COUNTERS]; /* counter order */
+ struct perf_event *event_list[TILE_MAX_COUNTERS]; /* enabled
+ order */
+ int assign[TILE_MAX_COUNTERS];
+ unsigned long active_mask[BITS_TO_LONGS(TILE_MAX_COUNTERS)];
+ unsigned long used_mask;
+};
+
+/* TILE arch specific performance monitor unit */
+struct tile_pmu {
+ const char *name;
+ int version;
+ const int *hw_events; /* generic hw events table */
+ /* generic hw cache events table */
+ const int (*cache_events)[PERF_COUNT_HW_CACHE_MAX]
+ [PERF_COUNT_HW_CACHE_OP_MAX]
+ [PERF_COUNT_HW_CACHE_RESULT_MAX];
+ int (*map_hw_event)(u64); /*method used to map
+ hw events */
+ int (*map_cache_event)(u64); /*method used to map
+ cache events */
+
+ u64 max_period; /* max sampling period */
+ u64 cntval_mask; /* counter width mask */
+ int cntval_bits; /* counter width */
+ int max_events; /* max generic hw events
+ in map */
+ int num_counters; /* number base + aux counters */
+ int num_base_counters; /* number base counters */
+};
+
+DEFINE_PER_CPU(u64, perf_irqs);
+static DEFINE_PER_CPU(struct cpu_hw_events, cpu_hw_events);
+
+#define TILE_OP_UNSUPP (-1)
+
+#ifndef __tilegx__
+/* TILEPro hardware events map */
+static const int tile_hw_event_map[] = {
+ [PERF_COUNT_HW_CPU_CYCLES] = 0x01, /* ONE */
+ [PERF_COUNT_HW_INSTRUCTIONS] = 0x06, /* MP_BUNDLE_RETIRED */
+ [PERF_COUNT_HW_CACHE_REFERENCES] = TILE_OP_UNSUPP,
+ [PERF_COUNT_HW_CACHE_MISSES] = TILE_OP_UNSUPP,
+ [PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = 0x16, /*
+ MP_CONDITIONAL_BRANCH_ISSUED */
+ [PERF_COUNT_HW_BRANCH_MISSES] = 0x14, /*
+ MP_CONDITIONAL_BRANCH_MISSPREDICT */
+ [PERF_COUNT_HW_BUS_CYCLES] = TILE_OP_UNSUPP,
+};
+#else
+/* TILEGx hardware events map */
+static const int tile_hw_event_map[] = {
+ [PERF_COUNT_HW_CPU_CYCLES] = 0x181, /* ONE */
+ [PERF_COUNT_HW_INSTRUCTIONS] = 0xdb, /* INSTRUCTION_BUNDLE */
+ [PERF_COUNT_HW_CACHE_REFERENCES] = TILE_OP_UNSUPP,
+ [PERF_COUNT_HW_CACHE_MISSES] = TILE_OP_UNSUPP,
+ [PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = 0xd9, /*
+ COND_BRANCH_PRED_CORRECT */
+ [PERF_COUNT_HW_BRANCH_MISSES] = 0xda, /*
+ COND_BRANCH_PRED_INCORRECT */
+ [PERF_COUNT_HW_BUS_CYCLES] = TILE_OP_UNSUPP,
+};
+#endif
+
+#define C(x) PERF_COUNT_HW_CACHE_##x
+
+/*
+ * Generalized hw caching related hw_event table, filled
+ * in on a per model basis. A value of -1 means
+ * 'not supported', any other value means the
+ * raw hw_event ID.
+ */
+#ifndef __tilegx__
+/* TILEPro hardware cache event map */
+static const int tile_cache_event_map[PERF_COUNT_HW_CACHE_MAX]
+ [PERF_COUNT_HW_CACHE_OP_MAX]
+ [PERF_COUNT_HW_CACHE_RESULT_MAX] = {
+[C(L1D)] = {
+ [C(OP_READ)] = {
+ [C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+ [C(RESULT_MISS)] = 0x21, /* RD_MISS */
+ },
+ [C(OP_WRITE)] = {
+ [C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+ [C(RESULT_MISS)] = 0x22, /* WR_MISS */
+ },
+ [C(OP_PREFETCH)] = {
+ [C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+ [C(RESULT_MISS)] = TILE_OP_UNSUPP,
+ },
+},
+[C(L1I)] = {
+ [C(OP_READ)] = {
+ [C(RESULT_ACCESS)] = 0x12, /* MP_ICACHE_HIT_ISSUED */
+ [C(RESULT_MISS)] = TILE_OP_UNSUPP,
+ },
+ [C(OP_WRITE)] = {
+ [C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+ [C(RESULT_MISS)] = TILE_OP_UNSUPP,
+ },
+ [C(OP_PREFETCH)] = {
+ [C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+ [C(RESULT_MISS)] = TILE_OP_UNSUPP,
+ },
+},
+[C(LL)] = {
+ [C(OP_READ)] = {
+ [C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+ [C(RESULT_MISS)] = TILE_OP_UNSUPP,
+ },
+ [C(OP_WRITE)] = {
+ [C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+ [C(RESULT_MISS)] = TILE_OP_UNSUPP,
+ },
+ [C(OP_PREFETCH)] = {
+ [C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+ [C(RESULT_MISS)] = TILE_OP_UNSUPP,
+ },
+},
+[C(DTLB)] = {
+ [C(OP_READ)] = {
+ [C(RESULT_ACCESS)] = 0x1d, /* TLB_CNT */
+ [C(RESULT_MISS)] = 0x20, /* TLB_EXCEPTION */
+ },
+ [C(OP_WRITE)] = {
+ [C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+ [C(RESULT_MISS)] = TILE_OP_UNSUPP,
+ },
+ [C(OP_PREFETCH)] = {
+ [C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+ [C(RESULT_MISS)] = TILE_OP_UNSUPP,
+ },
+},
+[C(ITLB)] = {
+ [C(OP_READ)] = {
+ [C(RESULT_ACCESS)] = 0x13, /* MP_ITLB_HIT_ISSUED */
+ [C(RESULT_MISS)] = TILE_OP_UNSUPP,
+ },
+ [C(OP_WRITE)] = {
+ [C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+ [C(RESULT_MISS)] = TILE_OP_UNSUPP,
+ },
+ [C(OP_PREFETCH)] = {
+ [C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+ [C(RESULT_MISS)] = TILE_OP_UNSUPP,
+ },
+},
+[C(BPU)] = {
+ [C(OP_READ)] = {
+ [C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+ [C(RESULT_MISS)] = TILE_OP_UNSUPP,
+ },
+ [C(OP_WRITE)] = {
+ [C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+ [C(RESULT_MISS)] = TILE_OP_UNSUPP,
+ },
+ [C(OP_PREFETCH)] = {
+ [C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+ [C(RESULT_MISS)] = TILE_OP_UNSUPP,
+ },
+},
+};
+#else
+/* TILEGx hardware events map */
+static const int tile_cache_event_map[PERF_COUNT_HW_CACHE_MAX]
+ [PERF_COUNT_HW_CACHE_OP_MAX]
+ [PERF_COUNT_HW_CACHE_RESULT_MAX] = {
+[C(L1D)] = {
+ /*
+ * Like some other architectures (e.g. ARM), the performance
+ * counters don't differentiate between read and write
+ * accesses/misses, so this isn't strictly correct, but it's the
+ * best we can do. Writes and reads get combined.
+ */
+ [C(OP_READ)] = {
+ [C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+ [C(RESULT_MISS)] = 0x44, /* RD_MISS */
+ },
+ [C(OP_WRITE)] = {
+ [C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+ [C(RESULT_MISS)] = 0x45, /* WR_MISS */
+ },
+ [C(OP_PREFETCH)] = {
+ [C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+ [C(RESULT_MISS)] = TILE_OP_UNSUPP,
+ },
+},
+[C(L1I)] = {
+ [C(OP_READ)] = {
+ [C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+ [C(RESULT_MISS)] = TILE_OP_UNSUPP,
+ },
+ [C(OP_WRITE)] = {
+ [C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+ [C(RESULT_MISS)] = TILE_OP_UNSUPP,
+ },
+ [C(OP_PREFETCH)] = {
+ [C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+ [C(RESULT_MISS)] = TILE_OP_UNSUPP,
+ },
+},
+[C(LL)] = {
+ [C(OP_READ)] = {
+ [C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+ [C(RESULT_MISS)] = TILE_OP_UNSUPP,
+ },
+ [C(OP_WRITE)] = {
+ [C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+ [C(RESULT_MISS)] = TILE_OP_UNSUPP,
+ },
+ [C(OP_PREFETCH)] = {
+ [C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+ [C(RESULT_MISS)] = TILE_OP_UNSUPP,
+ },
+},
+[C(DTLB)] = {
+ [C(OP_READ)] = {
+ [C(RESULT_ACCESS)] = 0x40, /* TLB_CNT */
+ [C(RESULT_MISS)] = 0x43, /* TLB_EXCEPTION */
+ },
+ [C(OP_WRITE)] = {
+ [C(RESULT_ACCESS)] = 0x40, /* TLB_CNT */
+ [C(RESULT_MISS)] = 0x43, /* TLB_EXCEPTION */
+ },
+ [C(OP_PREFETCH)] = {
+ [C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+ [C(RESULT_MISS)] = TILE_OP_UNSUPP,
+ },
+},
+[C(ITLB)] = {
+ [C(OP_READ)] = {
+ [C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+ [C(RESULT_MISS)] = 0xd4, /* ITLB_MISS_INT */
+ },
+ [C(OP_WRITE)] = {
+ [C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+ [C(RESULT_MISS)] = 0xd4, /* ITLB_MISS_INT */
+ },
+ [C(OP_PREFETCH)] = {
+ [C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+ [C(RESULT_MISS)] = TILE_OP_UNSUPP,
+ },
+},
+[C(BPU)] = {
+ [C(OP_READ)] = {
+ [C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+ [C(RESULT_MISS)] = TILE_OP_UNSUPP,
+ },
+ [C(OP_WRITE)] = {
+ [C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+ [C(RESULT_MISS)] = TILE_OP_UNSUPP,
+ },
+ [C(OP_PREFETCH)] = {
+ [C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+ [C(RESULT_MISS)] = TILE_OP_UNSUPP,
+ },
+},
+};
+#endif
+
+static atomic_t tile_active_events;
+static DEFINE_MUTEX(perf_intr_reserve_mutex);
+
+static int tile_map_hw_event(u64 config);
+static int tile_map_cache_event(u64 config);
+
+static int tile_pmu_handle_irq(struct pt_regs *regs, int fault);
+
+/*
+ * To avoid new_raw_count getting larger then pre_raw_count
+ * in tile_perf_event_update(), we limit the value of max_period to 2^31 - 1.
+ */
+static const struct tile_pmu tilepmu = {
+#ifndef __tilegx__
+ .name = "tilepro",
+#else
+ .name = "tilegx",
+#endif
+ .max_events = ARRAY_SIZE(tile_hw_event_map),
+ .map_hw_event = tile_map_hw_event,
+ .hw_events = tile_hw_event_map,
+ .map_cache_event = tile_map_cache_event,
+ .cache_events = &tile_cache_event_map,
+ .cntval_bits = 32,
+ .cntval_mask = (1ULL << 32) - 1,
+ .max_period = (1ULL << 31) - 1,
+ .num_counters = TILE_MAX_COUNTERS,
+ .num_base_counters = TILE_BASE_COUNTERS,
+};
+
+static const struct tile_pmu *tile_pmu __read_mostly;
+
+/*
+ * Check whether perf event is enabled.
+ */
+int tile_perf_enabled(void)
+{
+ return atomic_read(&tile_active_events) != 0;
+}
+
+/*
+ * Read Performance Counters.
+ */
+static inline u64 read_counter(int idx)
+{
+ u64 val = 0;
+
+ /* __insn_mfspr() only takes an immediate argument */
+ switch (idx) {
+ case PERF_COUNT_0_IDX:
+ val = __insn_mfspr(SPR_PERF_COUNT_0);
+ break;
+ case PERF_COUNT_1_IDX:
+ val = __insn_mfspr(SPR_PERF_COUNT_1);
+ break;
+ case AUX_PERF_COUNT_0_IDX:
+ val = __insn_mfspr(SPR_AUX_PERF_COUNT_0);
+ break;
+ case AUX_PERF_COUNT_1_IDX:
+ val = __insn_mfspr(SPR_AUX_PERF_COUNT_1);
+ break;
+ default:
+ WARN_ON_ONCE(idx > AUX_PERF_COUNT_1_IDX ||
+ idx < PERF_COUNT_0_IDX);
+ }
+
+ return val;
+}
+
+/*
+ * Write Performance Counters.
+ */
+static inline void write_counter(int idx, u64 value)
+{
+ /* __insn_mtspr() only takes an immediate argument */
+ switch (idx) {
+ case PERF_COUNT_0_IDX:
+ __insn_mtspr(SPR_PERF_COUNT_0, value);
+ break;
+ case PERF_COUNT_1_IDX:
+ __insn_mtspr(SPR_PERF_COUNT_1, value);
+ break;
+ case AUX_PERF_COUNT_0_IDX:
+ __insn_mtspr(SPR_AUX_PERF_COUNT_0, value);
+ break;
+ case AUX_PERF_COUNT_1_IDX:
+ __insn_mtspr(SPR_AUX_PERF_COUNT_1, value);
+ break;
+ default:
+ WARN_ON_ONCE(idx > AUX_PERF_COUNT_1_IDX ||
+ idx < PERF_COUNT_0_IDX);
+ }
+}
+
+/*
+ * Enable performance event by setting
+ * Performance Counter Control registers.
+ */
+static inline void tile_pmu_enable_event(struct perf_event *event)
+{
+ struct hw_perf_event *hwc = &event->hw;
+ unsigned long cfg, mask;
+ int shift, idx = hwc->idx;
+
+ /*
+ * prevent early activation from tile_pmu_start() in hw_perf_enable
+ */
+
+ if (WARN_ON_ONCE(idx == -1))
+ return;
+
+ if (idx < tile_pmu->num_base_counters)
+ cfg = __insn_mfspr(SPR_PERF_COUNT_CTL);
+ else
+ cfg = __insn_mfspr(SPR_AUX_PERF_COUNT_CTL);
+
+ switch (idx) {
+ case PERF_COUNT_0_IDX:
+ case AUX_PERF_COUNT_0_IDX:
+ mask = TILE_EVENT_MASK;
+ shift = 0;
+ break;
+ case PERF_COUNT_1_IDX:
+ case AUX_PERF_COUNT_1_IDX:
+ mask = TILE_EVENT_MASK << 16;
+ shift = 16;
+ break;
+ default:
+ WARN_ON_ONCE(idx < PERF_COUNT_0_IDX ||
+ idx > AUX_PERF_COUNT_1_IDX);
+ return;
+ }
+
+ /* Clear mask bits to enable the event. */
+ cfg &= ~mask;
+ cfg |= hwc->config << shift;
+
+ if (idx < tile_pmu->num_base_counters)
+ __insn_mtspr(SPR_PERF_COUNT_CTL, cfg);
+ else
+ __insn_mtspr(SPR_AUX_PERF_COUNT_CTL, cfg);
+}
+
+/*
+ * Disable performance event by clearing
+ * Performance Counter Control registers.
+ */
+static inline void tile_pmu_disable_event(struct perf_event *event)
+{
+ struct hw_perf_event *hwc = &event->hw;
+ unsigned long cfg, mask;
+ int idx = hwc->idx;
+
+ if (idx == -1)
+ return;
+
+ if (idx < tile_pmu->num_base_counters)
+ cfg = __insn_mfspr(SPR_PERF_COUNT_CTL);
+ else
+ cfg = __insn_mfspr(SPR_AUX_PERF_COUNT_CTL);
+
+ switch (idx) {
+ case PERF_COUNT_0_IDX:
+ case AUX_PERF_COUNT_0_IDX:
+ mask = TILE_PLM_MASK;
+ break;
+ case PERF_COUNT_1_IDX:
+ case AUX_PERF_COUNT_1_IDX:
+ mask = TILE_PLM_MASK << 16;
+ break;
+ default:
+ WARN_ON_ONCE(idx < PERF_COUNT_0_IDX ||
+ idx > AUX_PERF_COUNT_1_IDX);
+ return;
+ }
+
+ /* Set mask bits to disable the event. */
+ cfg |= mask;
+
+ if (idx < tile_pmu->num_base_counters)
+ __insn_mtspr(SPR_PERF_COUNT_CTL, cfg);
+ else
+ __insn_mtspr(SPR_AUX_PERF_COUNT_CTL, cfg);
+}
+
+/*
+ * Propagate event elapsed time into the generic event.
+ * Can only be executed on the CPU where the event is active.
+ * Returns the delta events processed.
+ */
+static u64 tile_perf_event_update(struct perf_event *event)
+{
+ struct hw_perf_event *hwc = &event->hw;
+ int shift = 64 - tile_pmu->cntval_bits;
+ u64 prev_raw_count, new_raw_count;
+ u64 oldval;
+ int idx = hwc->idx;
+ u64 delta;
+
+ /*
+ * Careful: an NMI might modify the previous event value.
+ *
+ * Our tactic to handle this is to first atomically read and
+ * exchange a new raw count - then add that new-prev delta
+ * count to the generic event atomically:
+ */
+again:
+ prev_raw_count = local64_read(&hwc->prev_count);
+ new_raw_count = read_counter(idx);
+
+ oldval = local64_cmpxchg(&hwc->prev_count, prev_raw_count,
+ new_raw_count);
+ if (oldval != prev_raw_count)
+ goto again;
+
+ /*
+ * Now we have the new raw value and have updated the prev
+ * timestamp already. We can now calculate the elapsed delta
+ * (event-)time and add that to the generic event.
+ *
+ * Careful, not all hw sign-extends above the physical width
+ * of the count.
+ */
+ delta = (new_raw_count << shift) - (prev_raw_count << shift);
+ delta >>= shift;
+
+ local64_add(delta, &event->count);
+ local64_sub(delta, &hwc->period_left);
+
+ return new_raw_count;
+}
+
+/*
+ * Set the next IRQ period, based on the hwc->period_left value.
+ * To be called with the event disabled in hw:
+ */
+static int tile_event_set_period(struct perf_event *event)
+{
+ struct hw_perf_event *hwc = &event->hw;
+ int idx = hwc->idx;
+ s64 left = local64_read(&hwc->period_left);
+ s64 period = hwc->sample_period;
+ int ret = 0;
+
+ /*
+ * If we are way outside a reasonable range then just skip forward:
+ */
+ if (unlikely(left <= -period)) {
+ left = period;
+ local64_set(&hwc->period_left, left);
+ hwc->last_period = period;
+ ret = 1;
+ }
+
+ if (unlikely(left <= 0)) {
+ left += period;
+ local64_set(&hwc->period_left, left);
+ hwc->last_period = period;
+ ret = 1;
+ }
+ if (left > tile_pmu->max_period)
+ left = tile_pmu->max_period;
+
+ /*
+ * The hw event starts counting from this event offset,
+ * mark it to be able to extra future deltas:
+ */
+ local64_set(&hwc->prev_count, (u64)-left);
+
+ write_counter(idx, (u64)(-left) & tile_pmu->cntval_mask);
+
+ perf_event_update_userpage(event);
+
+ return ret;
+}
+
+/*
+ * Stop the event but do not release the PMU counter
+ */
+static void tile_pmu_stop(struct perf_event *event, int flags)
+{
+ struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
+ struct hw_perf_event *hwc = &event->hw;
+ int idx = hwc->idx;
+
+ if (__test_and_clear_bit(idx, cpuc->active_mask)) {
+ tile_pmu_disable_event(event);
+ cpuc->events[hwc->idx] = NULL;
+ WARN_ON_ONCE(hwc->state & PERF_HES_STOPPED);
+ hwc->state |= PERF_HES_STOPPED;
+ }
+
+ if ((flags & PERF_EF_UPDATE) && !(hwc->state & PERF_HES_UPTODATE)) {
+ /*
+ * Drain the remaining delta count out of a event
+ * that we are disabling:
+ */
+ tile_perf_event_update(event);
+ hwc->state |= PERF_HES_UPTODATE;
+ }
+}
+
+/*
+ * Start an event (without re-assigning counter)
+ */
+static void tile_pmu_start(struct perf_event *event, int flags)
+{
+ struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
+ int idx = event->hw.idx;
+
+ if (WARN_ON_ONCE(!(event->hw.state & PERF_HES_STOPPED)))
+ return;
+
+ if (WARN_ON_ONCE(idx == -1))
+ return;
+
+ if (flags & PERF_EF_RELOAD) {
+ WARN_ON_ONCE(!(event->hw.state & PERF_HES_UPTODATE));
+ tile_event_set_period(event);
+ }
+
+ event->hw.state = 0;
+
+ cpuc->events[idx] = event;
+ __set_bit(idx, cpuc->active_mask);
+
+ unmask_pmc_interrupts();
+
+ tile_pmu_enable_event(event);
+
+ perf_event_update_userpage(event);
+}
+
+/*
+ * Add a single event to the PMU.
+ *
+ * The event is added to the group of enabled events
+ * but only if it can be scehduled with existing events.
+ */
+static int tile_pmu_add(struct perf_event *event, int flags)
+{
+ struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
+ struct hw_perf_event *hwc;
+ unsigned long mask;
+ int b, max_cnt;
+
+ hwc = &event->hw;
+
+ /*
+ * We are full.
+ */
+ if (cpuc->n_events == tile_pmu->num_counters)
+ return -ENOSPC;
+
+ cpuc->event_list[cpuc->n_events] = event;
+ cpuc->n_events++;
+
+ hwc->state = PERF_HES_UPTODATE | PERF_HES_STOPPED;
+ if (!(flags & PERF_EF_START))
+ hwc->state |= PERF_HES_ARCH;
+
+ /*
+ * Find first empty counter.
+ */
+ max_cnt = tile_pmu->num_counters;
+ mask = ~cpuc->used_mask;
+
+ /* Find next free counter. */
+ b = find_next_bit(&mask, max_cnt, 0);
+
+ /* Should not happen. */
+ if (WARN_ON_ONCE(b == max_cnt))
+ return -ENOSPC;
+
+ /*
+ * Assign counter to event.
+ */
+ event->hw.idx = b;
+ __set_bit(b, &cpuc->used_mask);
+
+ /*
+ * Start if requested.
+ */
+ if (flags & PERF_EF_START)
+ tile_pmu_start(event, PERF_EF_RELOAD);
+
+ return 0;
+}
+
+/*
+ * Delete a single event from the PMU.
+ *
+ * The event is deleted from the group of enabled events.
+ * If it is the last event, disable PMU interrupt.
+ */
+static void tile_pmu_del(struct perf_event *event, int flags)
+{
+ struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
+ int i;
+
+ /*
+ * Remove event from list, compact list if necessary.
+ */
+ for (i = 0; i < cpuc->n_events; i++) {
+ if (cpuc->event_list[i] == event) {
+ while (++i < cpuc->n_events)
+ cpuc->event_list[i-1] = cpuc->event_list[i];
+ --cpuc->n_events;
+ cpuc->events[event->hw.idx] = NULL;
+ __clear_bit(event->hw.idx, &cpuc->used_mask);
+ tile_pmu_stop(event, PERF_EF_UPDATE);
+ break;
+ }
+ }
+ /*
+ * If there are no events left, then mask PMU interrupt.
+ */
+ if (cpuc->n_events == 0)
+ mask_pmc_interrupts();
+ perf_event_update_userpage(event);
+}
+
+/*
+ * Propagate event elapsed time into the event.
+ */
+static inline void tile_pmu_read(struct perf_event *event)
+{
+ tile_perf_event_update(event);
+}
+
+/*
+ * Map generic events to Tile PMU.
+ */
+static int tile_map_hw_event(u64 config)
+{
+ if (config >= tile_pmu->max_events)
+ return -EINVAL;
+ return tile_pmu->hw_events[config];
+}
+
+/*
+ * Map generic hardware cache events to Tile PMU.
+ */
+static int tile_map_cache_event(u64 config)
+{
+ unsigned int cache_type, cache_op, cache_result;
+ int code;
+
+ if (!tile_pmu->cache_events)
+ return -ENOENT;
+
+ cache_type = (config >> 0) & 0xff;
+ if (cache_type >= PERF_COUNT_HW_CACHE_MAX)
+ return -EINVAL;
+
+ cache_op = (config >> 8) & 0xff;
+ if (cache_op >= PERF_COUNT_HW_CACHE_OP_MAX)
+ return -EINVAL;
+
+ cache_result = (config >> 16) & 0xff;
+ if (cache_result >= PERF_COUNT_HW_CACHE_RESULT_MAX)
+ return -EINVAL;
+
+ code = (*tile_pmu->cache_events)[cache_type][cache_op][cache_result];
+ if (code == TILE_OP_UNSUPP)
+ return -EINVAL;
+
+ return code;
+}
+
+static void tile_event_destroy(struct perf_event *event)
+{
+ if (atomic_dec_return(&tile_active_events) == 0)
+ release_pmc_hardware();
+}
+
+static int __tile_event_init(struct perf_event *event)
+{
+ struct perf_event_attr *attr = &event->attr;
+ struct hw_perf_event *hwc = &event->hw;
+ int code;
+
+ switch (attr->type) {
+ case PERF_TYPE_HARDWARE:
+ code = tile_pmu->map_hw_event(attr->config);
+ break;
+ case PERF_TYPE_HW_CACHE:
+ code = tile_pmu->map_cache_event(attr->config);
+ break;
+ case PERF_TYPE_RAW:
+ code = attr->config & TILE_EVENT_MASK;
+ break;
+ default:
+ /* Should not happen. */
+ return -EOPNOTSUPP;
+ }
+
+ if (code < 0)
+ return code;
+
+ hwc->config = code;
+ hwc->idx = -1;
+
+ if (attr->exclude_user)
+ hwc->config |= TILE_CTL_EXCL_USER;
+
+ if (attr->exclude_kernel)
+ hwc->config |= TILE_CTL_EXCL_KERNEL;
+
+ if (attr->exclude_hv)
+ hwc->config |= TILE_CTL_EXCL_HV;
+
+ if (!hwc->sample_period) {
+ hwc->sample_period = tile_pmu->max_period;
+ hwc->last_period = hwc->sample_period;
+ local64_set(&hwc->period_left, hwc->sample_period);
+ }
+ event->destroy = tile_event_destroy;
+ return 0;
+}
+
+static int tile_event_init(struct perf_event *event)
+{
+ int err = 0;
+ perf_irq_t old_irq_handler = NULL;
+
+ if (atomic_inc_return(&tile_active_events) == 1)
+ old_irq_handler = reserve_pmc_hardware(tile_pmu_handle_irq);
+
+ if (old_irq_handler) {
+ pr_warn("PMC hardware busy (reserved by oprofile)\n");
+
+ atomic_dec(&tile_active_events);
+ return -EBUSY;
+ }
+
+ switch (event->attr.type) {
+ case PERF_TYPE_RAW:
+ case PERF_TYPE_HARDWARE:
+ case PERF_TYPE_HW_CACHE:
+ break;
+
+ default:
+ return -ENOENT;
+ }
+
+ err = __tile_event_init(event);
+ if (err) {
+ if (event->destroy)
+ event->destroy(event);
+ }
+ return err;
+}
+
+static struct pmu tilera_pmu = {
+ .event_init = tile_event_init,
+ .add = tile_pmu_add,
+ .del = tile_pmu_del,
+
+ .start = tile_pmu_start,
+ .stop = tile_pmu_stop,
+
+ .read = tile_pmu_read,
+};
+
+/*
+ * PMU's IRQ handler, PMU has 2 interrupts, they share the same handler.
+ */
+int tile_pmu_handle_irq(struct pt_regs *regs, int fault)
+{
+ struct perf_sample_data data;
+ struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
+ struct perf_event *event;
+ struct hw_perf_event *hwc;
+ u64 val;
+ unsigned long status;
+ int bit;
+
+ __get_cpu_var(perf_irqs)++;
+
+ if (!atomic_read(&tile_active_events))
+ return 0;
+
+ status = pmc_get_overflow();
+ pmc_ack_overflow(status);
+
+ for_each_set_bit(bit, &status, tile_pmu->num_counters) {
+
+ event = cpuc->events[bit];
+
+ if (!event)
+ continue;
+
+ if (!test_bit(bit, cpuc->active_mask))
+ continue;
+
+ hwc = &event->hw;
+
+ val = tile_perf_event_update(event);
+ if (val & (1ULL << (tile_pmu->cntval_bits - 1)))
+ continue;
+
+ perf_sample_data_init(&data, 0, event->hw.last_period);
+ if (!tile_event_set_period(event))
+ continue;
+
+ if (perf_event_overflow(event, &data, regs))
+ tile_pmu_stop(event, 0);
+ }
+
+ return 0;
+}
+
+static bool __init supported_pmu(void)
+{
+ tile_pmu = &tilepmu;
+ return true;
+}
+
+int __init init_hw_perf_events(void)
+{
+ supported_pmu();
+ perf_pmu_register(&tilera_pmu, "cpu", PERF_TYPE_RAW);
+ return 0;
+}
+arch_initcall(init_hw_perf_events);
+
+/* Callchain handling code. */
+
+/*
+ * Tile specific backtracing code for perf_events.
+ */
+static inline void perf_callchain(struct perf_callchain_entry *entry,
+ struct pt_regs *regs)
+{
+ struct KBacktraceIterator kbt;
+ unsigned int i;
+
+ /*
+ * Get the address just after the "jalr" instruction that
+ * jumps to the handler for a syscall. When we find this
+ * address in a backtrace, we silently ignore it, which gives
+ * us a one-step backtrace connection from the sys_xxx()
+ * function in the kernel to the xxx() function in libc.
+ * Otherwise, we lose the ability to properly attribute time
+ * from the libc calls to the kernel implementations, since
+ * oprofile only considers PCs from backtraces a pair at a time.
+ */
+ unsigned long handle_syscall_pc = handle_syscall_link_address();
+
+ KBacktraceIterator_init(&kbt, NULL, regs);
+ kbt.profile = 1;
+
+ /*
+ * The sample for the pc is already recorded. Now we are adding the
+ * address of the callsites on the stack. Our iterator starts
+ * with the frame of the (already sampled) call site. If our
+ * iterator contained a "return address" field, we could have just
+ * used it and wouldn't have needed to skip the first
+ * frame. That's in effect what the arm and x86 versions do.
+ * Instead we peel off the first iteration to get the equivalent
+ * behavior.
+ */
+
+ if (KBacktraceIterator_end(&kbt))
+ return;
+ KBacktraceIterator_next(&kbt);
+
+ /*
+ * Set stack depth to 16 for user and kernel space respectively, that
+ * is, total 32 stack frames.
+ */
+ for (i = 0; i < 16; ++i) {
+ unsigned long pc;
+ if (KBacktraceIterator_end(&kbt))
+ break;
+ pc = kbt.it.pc;
+ if (pc != handle_syscall_pc)
+ perf_callchain_store(entry, pc);
+ KBacktraceIterator_next(&kbt);
+ }
+}
+
+void perf_callchain_user(struct perf_callchain_entry *entry,
+ struct pt_regs *regs)
+{
+ perf_callchain(entry, regs);
+}
+
+void perf_callchain_kernel(struct perf_callchain_entry *entry,
+ struct pt_regs *regs)
+{
+ perf_callchain(entry, regs);
+}